The present invention relates generally to head actuators and to disk storage devices having head actuators, and more particularly to a rotary head actuator pivotable around a shaft and a disk storage device having such a head actuator.
Among magnetic disk storages, hard disk storages have been used as memory means for computers. Hard disks have been more improved than so-called floppy disks in TPI (track per inch) and BPI (bit per inch) so that the hard disks can be recorded with high density. The hard disk is fixed in a sealed housing to prevent dust from the outside attaching itself thereto so that it can be recorded with high density. In such a hard disk storage, a rotary head actuator is usually used for it.
A rotary mechanism of a conventional head actuator comprises, as shown in FIG.1, a head supporting member 14 to which a head arm having magnetic heads at the top thereof (not shown) is attached, a shaft 15, bearing beds 16 and a yoke 17. The head supporting member 14 is coupled to the shaft 15 so that they are rotatable together. The shaft 15 is supported by the bearing beds 16 via the bearings 19, and the bearing beds 16 are fixed on the case 18. In addition, the yoke 17, which is used for a voice coil motor, is fixed on the case 18 apart from the head supporting member 14, the shaft 15 and the bearing beds 16. The yoke 17 is inserted into the case 18 from the side surface or the upper surface of the storage so as to be attached to the case 18.
However the conventional head actuator has the following disadvantages.
1. It is difficult to make the device thin because the bearing beds 16 which support the rotating shaft 15 must be provided in the direction of the thickness of the case 18.
2. Since the yoke 17 is made individually from other parts so as to be attached to the case 18, it is necessary to wait for a performance test of the voice coil motor until the actuator is completely assembled in the case 18, which is troublesome.
3. It is difficult to insert the yoke 17 into the case 18 from the side of the storage, and on the other hand, at least a screwing process will take longer if it is inserted from the upper surface thereof.
4. It is difficult to assemble the actuator in the case 18, thus the process for assembling it will take longer.